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arXiv · 2108.00156

Even-denominator fractional quantum Hall state in conventional triple-gated quantum point contact

Yasuaki Hayafuchi·Ryota Konno·Annisa Noorhidayati·Mohammad H. Fauzi·Naokazu Shibata·Katsushi Hashimoto·Yoshiro Hirayama
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Abstract

The even-denominator states have attracted considerable attention owing to their possible applications in future quantum technologies. In this letter, we first report a 3/2 diagonal resistance, indicating the existence of a 3/2 state in a nanometer-sized triple-gated quantum point contact (QPC) fabricated on a high-mobility (not ultra-high-mobility) single-layer two-dimensional (2D) GaAs wafer. The center gate plays a crucial role in realizing the QPC's 3/2 state. Our observation of the 3/2 state using a conventional QPC device, which is a suitable building block for semiconductor quantum devices, paves a new path for the development of semiconductor-based quantum technologies.

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Yasuaki Hayafuchi, Ryota Konno, Annisa Noorhidayati, Mohammad H. Fauzi, Naokazu Shibata, Katsushi Hashimoto, Yoshiro Hirayama. 2021-07-31. Even-denominator fractional quantum Hall state in conventional triple-gated quantum point contact. https://doi.org/10.35848/1882-0786%2Fac4c35

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